Flicker, stumble, dead. - BMW Forum

Raymond · 04-09-2010, 03:10 PM

I have an '89 325i vert. I've had it about two years. Car has been as dependable as sunrise. Yesterday while driving home at highway speed, the water temp gauge started to flick back and forth violently, and intermittently. It would waver franticly from off to just a tick above normal and settle to normal, then do it again and again irregularly. Engine was running fine.

When I got to surface roads and stopped at a traffic light, the gauge was stable and all seemed normal until I tried to accelerate away. The car burbled and seemed starved for power until above 1200 RPM and then seemed fine. It ran normally in traffic. However, I found I had to keep the revs over 1500 while engaging the clutch or the car would stumble. It was all fine with higher RPM. Check of coolant level in the car was fine. Thermostat is about 9 months old.

This morning, it started right up but the idle seemed a bit rough and cycled up and down irregularly from about 800 to 1100 RPM. the green double arrow idiot light on the bottom row was flashing. I shut off the engine and checked for loose leads or air filter obstructions and found none. Then the car would not fire. Plenty of cranking, but not a hint of fire.

Where should I start looking? What is the green double arrow light? I've never seen it light up before.

darkhorse737 · 04-10-2010, 01:00 PM

when was last tune up? Or last service?

Raymond · 04-10-2010, 06:01 PM

The odometer died more than two years ago, so I do the oil every 4 months and all the other fluids and filters in the fall. The spark plugs look okay and the gap is normal. I'll change them tomorrow. Air filter is still clean. I replaced the radiator and thermostat last summer. I have other cars so I was averaging about 11K miles per year in the daily driver.

I'm thinking the ECU may have stopped thinking.

german-speed-demon · 04-10-2010, 08:22 PM

ECu, coilpack, wires, bad ground. pretty much in that order. check em and trace them until you have power to your plugs.

Raymond · 04-11-2010, 07:30 PM

Okay, riddle me this. Apart from looking at the spark plugs I didn't do anything and the car is back to normal. That worries me. Intermittent problems are the worst.

Leads me to further suspect the ECU, but the coil pack is a really good thought. Thanks.

german-speed-demon · 04-11-2010, 08:16 PM

anytime sir. it's what we're here for